褪黑素对心肌缺血再灌注损伤的保护作用

目的　探讨褪黑素增补于停搏液中对缺血再灌注离体鼠心的保护作用。方法　将 2 4只 Wistar大鼠随机分为褪黑素组 (A )和对照组 (B)。离体鼠心在改良的 L angendorff- Neely灌注模型上 30分钟预灌注 ,12 0分钟停搏 ,30分钟再灌注。缺血前及再灌注期间测定血流动力学指标、心肌酶 (包括 CPK、L DH)、心肌超氧化物歧化酶 (SOD)、过氧化脂质 (L PO)含量。电镜观察心肌超微结构。结果　再灌注后 ,A组心功能、心肌超微结构的改善明显优于 B组 ;心肌酶 (CPK,L DH)、过氧化脂质 (L PO)含量显著低于 B组 (P<0 .0 1) ;心肌超氧化物歧化酶 (SOD)含量显著高于 B组 (P<0 .0 1)。结论　褪黑素增补于停搏液中可显著减轻心肌缺血再灌注损伤 ,具有良好的心肌保护作用

Protective effects of melatonin on myocardial ischemia-reperfusion injury

ObjectiveTo study the protective effects of melatonin on myocardial ischemia reperfusion injury. Methods The study consisted of two groups of rats. Group A ( n =12),received cardioplegia with melatonin. Group B( n =12),received same cardioplegia only. Isolated rat hearts were subjected to preperfusion for 30 min, ischemia for 120 min and reperfusion for 30 min using a modified Langendorff Neely model with modified Krebs Henseleit buffer at 37 ℃.The hemodynamic parameters, including myocardial enzyme (CPK, LDH), myocardial superoxide dismutase (SOD), myocardial lipid peroxide (LPO) and myocardial ultrastructure were measured before ischemia and during reperfusion.Results Recovery of cardial function and myocardial ultrastructure in Group A was significantly better than Group B. Myocardial enzyme (CPK, LDH) and myocardial lipid peroxide (LPO)in group A was significantly lower than in Group B ( P <0.01). Myocardial superoxide dismutase (SOD) was significantly higher than Group B ( P <0.01).Conclusion Melatonin supplement in cardioplegia significantly alleviated reperfusion mediated myocardial injury after global ischemia, suggesting good myocardioprotective actions.